RMGA Pipeline Operations and Maintenance 2 — Questions and Answers
Question 1: What is the purpose of a pressure regulating station in a gas distribution system?
- To add odorant to the gas
- To reduce transmission pressure to distribution pressure (Correct answer)
- To measure gas volume for billing
- To filter particulates from the gas stream
Correct answer: To reduce transmission pressure to distribution pressure
A pressure regulating station reduces high-pressure transmission gas to lower pressures suitable for distribution to customers.
Question 2: Which inspection method uses magnetic flux leakage to detect pipeline defects?
- Hydrostatic testing
- Acoustic emission testing
- In-line inspection with an ILI tool (Correct answer)
- Visual inspection with a CCTV camera
Correct answer: In-line inspection with an ILI tool
In-line inspection (ILI) tools using magnetic flux leakage travel inside the pipeline and detect wall loss, corrosion, and other anomalies.
Question 3: What is the minimum depth of cover required for a steel gas transmission pipeline installed in a Class 1 location under 49 CFR Part 192?
- 12 inches
- 18 inches
- 24 inches (Correct answer)
- 36 inches
Correct answer: 24 inches
49 CFR Part 192 requires a minimum cover of 24 inches for transmission pipelines in Class 1 locations.
Question 4: What does 'class location' determine for natural gas transmission pipelines?
- The chemical composition of the gas
- Design pressure and safety requirements based on population density (Correct answer)
- The required pipe material grade
- The frequency of odorant injection
Correct answer: Design pressure and safety requirements based on population density
Class location is based on the number of buildings intended for human occupancy within a pipeline corridor and determines design and operating requirements.
Question 5: What is the purpose of a relief valve on a gas pressure regulator?
- To increase outlet pressure during peak demand
- To release excess pressure if the regulator fails to maintain set pressure (Correct answer)
- To measure gas flow through the regulator
- To filter moisture from the gas stream
Correct answer: To release excess pressure if the regulator fails to maintain set pressure
A relief valve protects downstream piping by venting gas when pressure exceeds a predetermined limit due to regulator failure.
Question 6: Which document must operators of gas pipelines maintain to record all maintenance and inspection activities?
- Operations and Maintenance Manual (Correct answer)
- Environmental Impact Statement
- Customer Service Record
- Annual Financial Report
Correct answer: Operations and Maintenance Manual
49 CFR Part 192 requires operators to maintain an Operations and Maintenance Manual documenting procedures and inspection records.
RMGA Pipeline Operations and Maintenance 2
What is the purpose of a pressure regulating station in a gas distribution system?